Emotion Engineering: A Scientific Approach For Understanding Game Appeal

[Is there a defining theory for game design? Kalisto and 10tacle designer Bura tries to create a 'periodic table of elements' for creating games - from surprise through dread and beyond.]

This is a very exciting time to be a video game designer.

Video game design is evolving from a barely understood activity done by
genius designers driven by their gut feelings, to a craft with shared
techniques and methodologies. A common vocabulary cobbled from various
fields (interface design, psychology, complex systems, physics, etc.)
is slowly emerging. Successes and failures are analyzed...

But it's still a big mess, a large toolbox where any designer can find
the right tool to confirm exactly what he believes in. There are no
universally accepted truths, only opinions about what makes a great
game, whether or not video games are an art form or whether there is an
effective method to teach video game design.

We lack ways to compare games in an objective manner, ways to describe
them in a shared language. Without proper description, there can be no
true understanding. Success in video games still hinges on applying
traditional techniques, copying, marketing, luck, or genius. And even if
success is achieved, there's no guarantee that we can know why it
happened.

Arts and sciences have rules and laws, not just techniques. But what are the rules of video game design?

Where are the formal tools we can use to better understand, analyze, and improve games?

How big is the game design space and can we identify its virgin territories?

What are the rules we can bend or break to create totally new experiences?

This article presents a theory of what video game game design is and explains how to find some of these rules.

Caveat: If I sound pedantic or over-confident in this
article, please prefix any affirmation I make with "I modestly believe
without being able to prove that..." This work has generated many hours
of doubt and self-doubt. I do not pretend to teach anyone the
definitive meaning of trust, catching-up, fear, or of collecting a
power-up. This is an ongoing work, as the article's version number - 1.0.4 - attests.
If you disagree with me, please tell me why and I'm sure you'll be
convincing enough to change my mind.

That said, let's start with easy questions that have clear answers: "What is game design?" and "What is a good game?"

What is Game Design?

Players don't play to complete games, just as readers don't read to
finish books. Players play to feel emotions. Game design is experience
crafting for the purpose of emotion engineering.

Game design is
intrinsically hard because its output is an interactive system that is
twice removed from its goal. The game designer produces rules for
interaction that, with the participation of the player, generate game
states that themselves induce emotions in the player.

Note: In Emotional Design,
Donald Norman describes three different levels of experience
processing: visceral (how it makes the person having the experience
feel), behavioral (how well it suits its purpose or function), and
reflective (how it affects the person’s self-image). Games can have a
behavioral aspect, from being a learning tool to a systemic
demonstration of a concept. This article focuses on the other two
aspects: how games can have an emotional impact on their players.

If we can describe a given game state using a set of gameplay variables, we get the following cycle:

Interactions between the player and the game produce changes in the gameplay variables. For instance, finding a heart container in Zelda and getting a bigger full health bar obviously changes something in the game state. We'll explore below what this could be.

Variations or stability of these variables induce emotions in the player. For instance, having a bigger full health bar could make him more confident.

Player's emotions influence how he interacts with the game. For
instance, being confident might make him take more risks; pride might
keep him chasing a high score; or boredom might make him stop playing
altogether.

Some of these emotions are the result of a carefully crafted
sequence of events. Others stem from the normal moment-to-moment
interaction with the game. Since the players and their playing
experiences are so different from one another, one cannot guarantee that
a given player will feel a given emotion at a given point in a game.
However, from our understanding of physiology, psychology, cognition, or
culture, we can identify situations that create the proper context for
the expression of such an emotion.

Note: This article is not about creating emotions with the content,
the subject matter, or the story, but through interactions with the game
alone. Indeed, these are integral parts of the whole - emotions are
enhanced by the appropriate setting or story - but the subject has been
talked about at length by better qualified people elsewhere. So I'll
skip this for now.

Game design works backwards around this cycle, trying to predict
player emotions from changes in the interactive system. But our
knowledge of the dependencies between interaction and emotion is so
sparse that most changes require testing. Testing in part requires
implementing the changes, which costs time and money. Thus, in a
professional setting where budget is an issue, game design innovation
can quickly become a risk.